Structure evolution towards 78Ni : challenges in the interpretation of hard-won experimental data
solved by simple means
David Verney, IPN Orsay
FUSTIPEN Topical Meeting -- « Recent Advances in the Nuclear Shell Model » -- June 19-20, 2014, GANIL, Caen
• An introduction to the N=50 shell effect/evolution towards 78Ni
• How and why the subject was introduced in Orsay
• What we have learned ?Selection of results (from Orsay and elsewhere) :
collectivity and evidence of intruder states in the 78Ni region
Page 2Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
• An introduction to the N=50 shell effect/evolution towards 78Ni
Page 3Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
The 78Ni region in 2014: the final cut (?)
Age of the pionneers: mid 80’s
TRISTAN(Brookhaven)/OSIRIS(Studsvik)
“Is the region above 78Ni doubly magic ?”r-process consequences
Fogelberg, J.C. Hill, J.A. Winger and others
The final cut ? : ca 2014
RIKEN
direct study of 78Ni
By Kratz et al. PRC 38 (1988)
Waiting point nucleus at N=50 80Zn
« » very busy decade
dormance
Second golden age : ca 2004
Yrast (LNL,Euroball)/Coulomb exc. (ISOLDE,ORNL)
/Masses (JYFL,ISOLDE)/transfer (ORNL,ISOLDE)
/Radioactivity(ORNL,Orsay)“Is N=50 a good magic number?”
r-process + structure consequences
Page 4Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
The persistence of N=50: the core-breaking states
32
p1/2
g9/2
d5/2
neutrons
50
O. Sorlin, M.G. Porquet Prog. Part. Nucl. Phys. 61 (2008) 602
N=50 gap extrapolation → 78Ni =3.0(5) MeV
After a decade : no (serious) evidence was found for shell quenching down to Z=30 in the low energy data (radioactivity and coulomb excitations studies). But:
Page 5Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
The question of the size of the gap at N=50: what masses sayusing data taken from AME2012[including Hakala et al. PRL101 052502 (2008)]
collective origintheoretically : Bender et al. Phys. Rev. C 78, 054312 (2008)
maximum influence of beyond mean-field correlations
D = S2n(52)-S2n(50)
extracted from
Bender et al. Phys. Rev. C 78, 054312 (2008)ed
5/2 –
eg 9/
2 (M
eV)
Ni Zn Ge Se Kr Sr
Duflo Zuker gap PRC59 (1999) 90Zr =4,7 MeV
Duflo Zuker gap 78Ni =5,7 MeV
« standard »« graphical »
loca
l min
imum
at Z
=32
Zr
K. Heyde et al. Phys. Let. B176 (1986) NPA466 (1987) 189
« standard »
« graphical »
Page 6Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
K. Sieja and F. Nowacki, Phys. Rev. C 85, 051301R (2012)
minimum in gap D
The question of the size of the gap at N=50: shell model
Page 7Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
NPA466 (1987) 189
Z
Sn(Z,N)-Sn(Z,N+1)
Sn(Z,N)-Sn(Z,Nextr)
N N+1 N+3 N+5 N+7neutron number
(Koopmans theorem)
gap in the single particle levels
n
50ej’n
ejn
-ej’n= Sn(Z,N)
but Sn(Z,N+1) is not a good prescription for
for the evaluation of ejn
one has to estimate ej’n and ejn in the same nucleus
ejn—ej’n = Sn(Z,N) —Sn(Z,Nextr) then the good prescription becomes :
The question of the size of the gap at N=50: back to core-breaking states
p1/2
g9/2
d5/2
neutrons
50
K. Heyde et al. graphical methodNPA466 (1987) 189
There are more things than monopole effects in the red curve …
Page 8Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
K. Sieja and F. Nowacki, Phys. Rev. C 85, 051301R (2012)
The question of the size of the gap at N=50: back to core-breaking states
Fusion-fission experiment accepted for AGATA@GANIL campaign (spokespersons G. Duchêne and G. De Angelis)search for core-breaking Yrast states in 80Zn
Page 9Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
figures taken from Bender et al. Phys. Rev. C 78, 054312 (2008)
N=50 vs Z=50 situations
Page 10Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
• How and why the subject was introduced in Orsay
(experimental context)
Page 11Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
Zn81
Present limit of structure knowledge(at least few excited states are known)
hot plasma ionization(1 µA deuteron primary beam)O. Perru PhD – def. 10th December 2004Eur. Phys. J. A 28, 307 (2006)+PhD A. Etile CSNSM ongoing
surface ionization (2-4 µA electron primary beam)M. Lebois PhD – def. 23th September 2008PRC 80, 044308 (2009) B. Tastet PhD – def. 13th May 2011PRC 87, 054307 (2013)D. Testov PhD – def. 17th January 2014
laser ionization(10 µA electron primary beam)K. Kolos PhD – def. September 2012PRC 88, 047301 (2013)
Ga84Ga83Ga82 Ga85Ga80Ga79
Ge80Ge79 Ge81 Ge85 Ge86
As82
hot plasma ionization(1 µA deuteron primary beam)PRC 76 (2007) 054312
-decay spectroscopyat the PARRNe mass separator (Tandem/ALTO)
Zn82
And “spin-off” elsewhere: -LNL :Plunger + AGATA + PRISMA-RIKEN: EURICA, MINOS campaignsaccepted : GANIL Plunger + AGATA + VAMOS LoI: SPES, SPIRAL2 phase 2
Page 12Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
Tandem building Institut de Physique Nucléaire Campus of the Paris Sud University Orsay (France)
Page 13Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
ALTO=ISOL installation based on photo-fission (the first of its kind in the world)
PARRNe mass separator
e-LINAC 10 µA 50MeV
(former 1st section of the
CERN LEP injector)
TIS vault>~1.10^11 fissions/s
Target Ion-source ensemble
kicker - bender
secondary beam lines
POLAREXnuclear
orientation on line
identification station
BEDObeta decay
spectroscopy
and the only facility in France providing fission fragments as mass separated RIBs (prefiguring for a time SPIRAL2.2)
Page 14Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
plastic scintilator
Large volume Ge detector(EUROGAM-1 French-UK loan pool)
Ge CLOVER (proto EXOGAM )
Mylar tape
beam
etotal(photo-peak 1.3MeV)~2%
T1/2 measurement: tape motion cyclingTriggerless DAQ 400ps resolution time stamping
time
decayion beam deviated
build upion collection
Detection setup and movable tape
Page 15Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
β energy loss
Compton
collection point
Ge
GeGe
plastic scintillator
4π-β
Ge
ancilaryplastic
BGO
4p beta
BEDO : BEta Decay studies at OrsayStrategy for optimal detection Compact geometry (max γ efficiency)
γ background suppression
BGO crystals
Page 16Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
BEDO : BEta Decay studies at Orsay construction completed – commissioning beam time in 2012
Anti-Compton belt
4 EXOGAM small prototypesSource-cap distance = 5 cmevaluated eg (1 MeV) = 3-4 % (previous system 1-2%)
sensitivity 0.1 pps
up to 5 Ge detectors
6 plastic detectors
beam entrance
Page 17Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
• What we have learned ?Selection of results,
collectivity and evidence of intruder states in the 78Ni region
Page 18Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
Zn81
surface ionizationB. Tastet PhD – def. 13th May 2011PRC 87, 054307 (2013)laser ionization(10 µA electron primary beam)K. Kolos PhD – def. September 2012PRC 88, 047301 (2013)D. Testov PhD – def. 17th January 2014
Ga84Ga83Ga82 Ga85Ga80Ga79
Ge80Ge79 Ge81 Ge85 Ge86
As82
Zn82
-decay spectroscopyaround the Z=32 “curiosity”
Page 19Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
isomerism in the N=49 line
(3-5) Hoff & Fogelberg NPA368 (1981)
8+6+
4+
2+
0+
(ng9/2-2)8+ seniority isomer
populated in DIC●Makishima et al PRC 59 (1999)●Podolyak et al Int. J. Mod phys E 13 (2004)●H. Mach et al J. Phys. G 31 (2005)
→ T1/2=2.95(6) ns
existence of second beta decaying state with I~7 suspected
ISOLDE experiment, laser spectroscopy : two long lived states in 80Ga I=3 and I=6 (negative parity from shell model)B. Cheal et al., PRC 82 (2010) 051302R
Page 20Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
Study of 80Ga→80Ge beta decayhi
ts p
er 0
.5 k
eV
Energy (keV)
Page 21Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
etc…Over the 75 γ-rays previously attributed to the 80Ga decay, the decay time of 67 individual β-delayed γ-activities were measured
the apparent half life of 30 levels could be determined
Study of 80Ga→80Ge beta decay
Page 22Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
measured half-life in seconds
T1/2=1.6870.011s Singh Nuclear Data sheets 105 (2005) 223apparent half-life of the 80Ge levels
longer lived
shorter livedHoff & Fogelberg 235U
ALTO
238 U
Study of 80Ga→80Ge beta decay
Page 23Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
80Galongershorter
80Ge
lA (apparent half life)
lL
longer lived state contribution
shorter lived state contribution
levels of 80Ge
lS
1 0,8 0,6 0,4 0,2 0
lF (indirect feeding apparent half life)
Study of 80Ga→80Ge beta decay
Page 24Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
80Galongershorter
T1/2= 1.90.1 s
T1/2= 1.30.2 s3―
6―
Study of 80Ga→80Ge beta decay
Page 25Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
M. Honma et al., Phys. Rev. C 80, 064323 (2009)
B.A. Brown private communication, as first used in D. V. et al. Phys. Rev. C 76, 054312 (2007)
JUN45 JJ4B
multipletsclose to the 0(6) limit of IBM
Page 26Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
Kumar model-independent n-body moments
[Kumar PRL28, 249 (1972)]
intrinsic shapes of SM eigenstates
JUN45 JJ4B
shell model calculations and transcription into intrinsic shapes
Page 27Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
microscopic origin of the collective features
JUN45 JJ4B
f5/2
p3/2
p1/2
g9/2
p nf5/2
p3/2
p1/2
g9/2
p n
collective gamma-soft configurations
f5/2
p3/2
p1/2
g9/2
p n
non-collectivequasi-particle like
configurations
Dℓ=2
quadrupole components of the interaction
pairing components of the interaction
►the energy proximity of f5/2 and p orbits (Dℓ=2) seems to be the key ingredient
energy separation between f5/2 and p3/2 in 79Cu :~1 MeV in JUN45 390 keV in JJ4B
Page 28Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
Triaxiality at Z=32
Page 29Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
76Ge
0+2 ?
Triaxiality at Z=32 and possible intruder 2p-2h 0+ states at N=48
“triaxial features” evolution of the 0+2 state energy
Page 30Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
80Ge 80Ge
from M. Honma et al., Phys. Rev. C 80, 064323 (2009)
Page 31Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
Zn81
laser ionization(10 µA electron primary beam)K. Kolos PhD – def. September 2012PRC 88, 047301 (2013)
Ga84Ga83Ga82 Ga85Ga80Ga79
Ge80Ge79 Ge81 Ge85 Ge86
As82
Zn82
-decay spectroscopyaround the Z=32 “curiosity”
Page 32Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
Lebois et al.
Kolos et al.
Study of 84Ga5384Ge52 decay
Page 33Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
(0—,1—)
Study of 84Ga5384Ge52 decay
Page 34Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
84Ga5384Ge52 : addressing the collectivity development beyond N=50
0 0+
2+710
1744 4+
6+3095
1542 22+
1934 02+
2838 23+
HFB-5DCH Gogny D1S Delaroche et al. Bruyères-le-Châtel, available online, S. Hilaire M. Girod
Page 36Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
0 0+
2+769
1584 4+
6+2900
1530 22+
42+21302002 31+
2812 51+
1768 02+
2150 24+
2603 43+
1873 23+
2360 32+
346
370
405
269
166
229231
599
77
137
145
0 0+
2+
(1+,2+)
(0+,1+,2+)
3502 (1+,2+)
EXP
2228
1389
624
JJ4B(proton-proton)+Sieja et al PRC 79, 064310 (2009)
g (°)
=
0 0+
2+710
1744 4+
6+3095
1542 22+
1934 02+
2838 23+
HFB-5DCH Gogny D1S
Page 37Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
A bit deeper into the problem of intruder states: odd isotones N=49
• What we have learned ?Selection of resultscollectivity and evidence of intruder states in the 78Ni region
Page 38Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
Zn81
Ga84Ga83Ga82 Ga85Ga80Ga79
Ge80Ge79 Ge81 Ge85 Ge86
As82
Zn82
PhD A. Etile (CSNSM Orsay) ongoingfirst data taken with the new -decay spectroscopy setup BEDO(BEDO commissioning)
odd-odd nuclei:- detailed spectroscopy: stopped beam experiments- -decay very selective as allowed GT transitions e-e→o-o practically exclusively 0+→1+
A bit deeper into the problem of intruder states: the case of the odd-odd N=49 isotones
Page 39Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
By Kratz et al. PRC 38 (1988)
Waiting point nucleus at N=50 80Zn
By Winger et al. PRC 36 (1987)
« »
The anomalous occurrence of low lying 1+ states in the odd-odd N=49 isotone 80Ga → historically launched the problematic of a possible vanishing of the N=50 shell effect
Page 40Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
Winger et al. PRC 36 (1987) Fig. taken from Kratz et al. PRC 38 (1988)
RPA calculations, with significant quadrupole deformation (ε2=0.26) produce naturally an enormous amount of 1+ states (2QP states, Nilsson labeled), which was found satisfactory (!)
in a similar study Winger et al removed the parenthesis only at much higher energy
Page 41Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
In the observation of the beta decay of an even-even to an odd-odd nucleus : one cannot (in principle) “miss” the lowest 1+ states (only 0+→1+ beta transitions are allowed in n-rich nuclei)
Q window
Eidens et al (1970)
Hoff & Fogelberg (1981)
Winger et al(1987)
note the huge increase in the number of states populated by beta decay between 82As and 80Ga-- is it real ? is there an important structure effect at play ?
Page 42Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
H. Gausemel et al., Phys. Rev. C 70, 037301 (2004)
3.4(9)
80(20)
1.6(5)
0.35(9)
B(%) log ft
5.7(2)
4.2(2)
5.3(2)
5.8(2)
3.5(
5)8.
50(6
)
1.45
(2)
<1<1
100(
3)
(0-,1-)
(0,1)
(0,1)
Study of 82Ge→82As beta decay
(Still a bit preliminary)
Page 43Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
what are the proton-neutron configurations one can expect at low energy ?→ let’s start with the zero-order coupling
O-ν
even-even semi-magic core
O-O O-π
E-Eproton open shell(proton quasi-particles)
neutron closed shell(neutron holes and intruder states)
odd-proton N=50 nucleus(taken from experimental level scheme)
odd-neutron N=49 nucleus(taken from experimental level scheme)
odd-odd N=49 nucleus(we hope to describe)
Page 44Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
Neutron statesOmnipresence of positive parity (intruder) statesFirst hinted at from transfer reaction data [e.g. Detorie et al PRC18 (1978)]First systematics proposed by Hoff & Fogelberg NPA 368 (1981)emphasized in Meyer et al. PRC 25 (1982) since then everybody has been quiet on the subject
1p-2h states2+ p1/2
-1 or f5/2-1,p3/2
-1 ?
78Zn(d,p) R. Orlandi et al. (REX-ISOLDE)79-80Cu -decay M. Niikura (EURICA RIKEN)
Page 45Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
A. Pfeiffer et al. NPA 455 (1986) 381
Proton states
Page 46Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
from beta-decayD.V. et al. PRC 76, 054312 (2007)
Proton states
5/2 assignment to ground state unambiguously confirmed from laser spectroscopy measurementsCheal et al PRL 104, 252502 (2010) N.B. We will know more soon:
79Cu has been populated in 80Zn(p,2p) reaction at RIKEN recently (PhD work in Orsay under the supervision of S. Franchoo)
Page 47Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
0
500
1000
1500
2000
2500
3000
3500
4000
86Rb 84Br 82As 80Ga
Ener
gy (k
eV)
f5*p3(+)
f5*f5(+)
p3*p1(+)
p3*p3(+)
p3*f5(+)
p1*p1(+)
p1*p3(+)
g9*g9(+)
0
500
1000
1500
2000
2500
3000
3500
4000
86Rb 84Br 82As 80Ga
Ener
gy (k
eV)
f5*d5(-)
f5*d3(-)
p3*d5(-)
p3*s1(-)
p3*d3(-)
p1*s1(-)
p1*d3(-)
82As is the first N=49 isotone for which low-spin negative parity (0- and 1-) states appear below the first 1+ state
Unperturbed positions of the proton-neutron configurations in the odd-odd N=49 isotones
normal positive parity intruder negative parity
Page 48Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
Include 2d5/2, 3s1/2, 2d3/2 on top of the fp-g valence space → very challenging for shell model, not yet available
→ what can be done ?
→ in a first approach, one can use a much less computationally demanding solution:core-particle coupling model
→ our job was facilitated and encouraged by :(1) The description of odd N=49 nuclei down to 85Kr, including 2d5/2, 3s1/2, 2d3/2 has already been
done: Kitching Z. Phys. 258 (1973) ; Bhattacharya & Basu J. Phys. G 5 (1979)
(2) Hoffmann-Pinther & Adams [NPA229 (1974)] have already treated the odd-odd case within the Thankappan-True [Phys. Rev. 137 (1965)] schematic approach
Core QP π QP ν C - π
C - ν
π-ν interactionexperimental values fit to the odd nucleistrength adjusted on
86Rb
Page 49Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
experimental
coupled to 0+
coupled to 2+
in agreement with identifications made by Dawson et al. Phys. Rev. 181 (1969)
Page 50Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
experimental
coupled to 0+
coupled to 2+
3.4(9)
80(20)
1.6(5)
0.35(9)
B(%) log ft
5.7(2)
4.2(2)
5.3(2)
5.8(2)
3.5(
5)8.
50(6
)
1.45
(2)
<1<1
100(
3)
(0-,1-)
(0,1)
(0,1)only states coupled to 2+
2+ core coupled states ?
(clearly) π p3/2 ν p1/2-1
intruder π f5/2 ν d5/2
Page 51Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
Winger et al. PRC 36 (1987) Fig. taken from Kratz et al. PRC 38 (1988)
RPA calculations, with significant quadrupole deformation (ε2=0.26) produce naturally an enormous amount of 1+ states (2QP states, Nilsson labeled), which was found satisfactory (!)
in a similar study Winger et al removed the parenthesis only at much higher energy
Page 52Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
Page 53Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
The 78Ni region in 2014: the final cut (?)
Age of the pionneers: mid 80’s
TRISTAN(Brookhaven)/OSIRIS(Studsvik)
“Is the region above 78Ni doubly magic ?”r-process consequences
Fogelberg, J.C. Hill, J.A. Winger and others
Second golden age : ca 2004
Yrast (LNL+Euroball)/Coulomb exc. (ISOLDE,ORNL)
/Masses (JYFL+ISOLDE)/transfer (ORNL,ISOLDE)
/Radioactivity(ORNL+Orsay)“Is N=50 a good magic number?”
r-process + structure consequences
Third golden age : ca 2014
RIKEN + elsewhere
direct study of 78Ni + around
very busy decade
dormance
towards an even busier decade
Conclusions• the question of the gap minimum Z=32, its microscopic origin and general consequences : we have just scratched the subject
• rapid energy increase of the p1/2 hole states below Z=32 (N=40 gap)
• Below Z=32, even at low energy, there is no hope shell model calculations can do a good job without including some external orbits (obvious statement but cruel necessity for experimentalists’ interpretations)
importance of the triaxial degree of freedom
AND the intruder states
Page 54Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
backup slides
Page 55Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
90’s ending, beginning 2000’s, ISOL activity back at IPN: PARRNe
converter(C)
deuteron beam(1µA 26 MeV)
fast neutrons
1+
ionsource
FissionFragments
target (10^9 fissions/s)
238U
fission
mass separator
detection
from P.W.Lisowski et al, OECD/NEA Report NEANDC-305 'U' 1991 p.177
Thesis Nicolas PauwelsIPN Orsay
initially a R&D test bench for the SPIRAL2 project
« Production d’Atomes Radioactifs Riches en Neutrons »
it all began with…
Page 56Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
exploratory photofission experiment at CERN
arrival of the LINAC cavity from decommissioned LEP injector
construction of the LINAC bunker
RF system
First e-beam extracted
UCx target on line with e-beam– production yields measurements
Commissioning : tests and radiation safety measurements
TIS vault
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
1999
1998
building of the low energy beam lines + laser ion source
2011
2012
2013
green light from French nuclear safety authorities
BEDO commissioning
first laser ionized RIB
83Ga -> 83Ge -decay
81Zn -> 81Ga -decay
84Ga -> 84Ge -decay
initial idea of a R&D test bench for the SPIRAL2 project at the Orsay Tandem
INAUGURATION
ISOL available at TANDEM PARRNe mass-separator on line
Page 57Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
BEDO
LINOlaser spectroscopy
POLAREX
TAS
TETRA
nuclear orientation on line (CSNSM)
Total Absorption Spectroscopy(Subatech Nantes, IFIC Valencia)
Pn measurements(IPN/FLNR)
The ISOL installation at ALTO short and medium term projects
Page 58Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
first experimental hint of proton evolution towards 78Nialong the N=50 linevery temptative, preliminary etc
p3/2
f5/2
28 29 30 31 32 33 34 35 36 37 38 39 40 41
-25
-20
-15
-10
-5
0
exactly consistent withPfeiffer et al. NPA 455 (1986) 381who provided sp energies, QP energies and v2.
prot
on E
SPS
(MeV
)
Z (N=50)
g9/2p1/2 Fermi level
f7/2
allows to explain the Jp of 80Ga and 80mGaISOLDE experiment, laser spectroscopy : two long lived states in 80Ga J=3 and J=6B. Cheal et al., PRC 82 (2010) 051302
extrapolation
Ga As BrCu Rb
Page 58/Verney – IPN Orsay Shell Model as Unified View of Nuclear Structure – 8-10 Oct. 2012
Page 59Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
0
1
2
3
4
5
6
7
8
f5p3p1g9
PRO
TON
SPE
(MeV
)
p3/2
f5/2
g9/2
p1/2
JW Lis JUN45 JJ4B
Ji et Wildenthal Phys. Rev. C 38, 2849 (1988)
A.F. Lisetskiy et alPhys. Rev. C 70, 044314 (2004)
M. Honma et alPhys. Rev. C 80, 064323 (2009)
A. Brown priv. com.used inVerney et al Phys. Rev. C 76, 054312 (2007)
may be useful for shell model calculations in the 78Ni region
fitted SPE
result from monopole migration (realistic N-N interactions)
Sieja & Nowacki Phys. Rev. C 81, 061303(R) (2010)
SN this work
Page 59/Verney – IPN Orsay Shell Model as Unified View of Nuclear Structure – 8-10 Oct. 2012
Page 60Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
Page 61Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
ng9/2np1/2
Z=37
Z=35
Z=33
Z=31
Z=29
N=49
78Ni
78Cu
80Ga
82As
84Br
86Rb
N=50
p3
f5 ●● ●● ●●●●● ○
p3
f5 ●● ●● ●●●
p3
f5 ●● ●● ●○
p3
f5 ●
○ ○○
p3
f5 ●● ●○ ○○
Z=38 88Sr
pp3/
2pf
5/2
90Zr
pp1/
2pg
9/2
nd5/2 ns1/2 nd3/2
np3/2
nf5/2 86Rb Dawson et al. Phys. Rev. 181 (1969)
2,3,4,5,6,7
3,4,5,6
Page 62Verney – IPN Orsay FUSTIPEN Topical Meeting –Caen June 19-20, 2014
ng9/2np1/2
Z=37
Z=35
Z=33
Z=31
Z=29
N=49
78Ni
78Cu
80Ga
82As
84Br
86Rb
N=50
pf5/2-1ng9/2
-1
pp3/2-1ng9/2
-1
pf5/2-1ng9/2
-1
pp3/2+1ng9/2
-1
pf5/2-1ng9/2
-1
pp3/2+1ng9/2
-1
pf5/2+1ng9/2
-1
pp3/2+1ng9/2
-1
pf5/2+1ng9/2
-1
pp3/2+1ng9/2
-1
p3
f5 ●● ●● ●●●●● ○
p3
f5 ●● ●● ●●●
p3
f5 ●● ●● ●○
p3
f5 ●
○ ○○
p3
f5 ●● ●○ ○○
p3/2 turns into particle character
f5/2 turns into particle character
Z=38 88Sr
pp3/
2pf
5/2
90Zr
pp1/
2pg
9/2
N=49
nd5/2 ns1/2 nd3/2
np3/2
nf5/2